Today, the first human successfully released the impactor hit the comet rehearsal completed.

<P> U.S. Eastern Time at 1:52 on July 4 (Beijing time at 13:52 on July 4), the night sky over the U.S. Independence Day fireworks will be dotted with numerous beautiful, but the most striking one .fireworks will bloom 132 million km from Earth at the space: NASA's "Deep Impact" space probe will send shock No. tank to 10.2 km / s impact speed of the universe comet Tempel One. .It can be seen with the naked eye even this little shiny space fireworks. .</ P> <P> cost of $ 333,000,000 in "Deep Impact" space probe number the tasks not just to create a beautiful man-made celestial phenomena, it is to answer for a long time human comet itself, the formation of the solar system, .many questions and even the origin of life. .</ P> <P> shells collide </ P> <P> Beijing at 14:07 on the 3rd or so, NASA's Jet Propulsion Laboratory announced that under the "Deep Impact" probe to release the impactor. .Subsequently received signals that the ground, nearly 400 pounds, about the size of the impactor household refrigerators and detectors have been separated, is flying to the comet nucleus. .Jet Propulsion Laboratory engineer, said data checking that everything is planned. .As planned, the impactor will "collide" 24 hours later, about 10 kilometers per second relative velocity bombardment of Tempel 1's nucleus. .</ P> <P> Purple Mountain Observatory, Chinese Academy of Sciences, according to researcher yesterday described the king thought: "You could say, for 4, will be staged in the 'shelling' comets, and related observations, Chinese and foreign scientists has completed the 'dress rehearsal'. Photo .the current situation, 'shelling' comets may be very good show. "thought the king said, NASA launched" Deep Impact "spacecraft progress all goes well, Chinese and foreign scientists have successfully observed by telescope A Temple .comet related conditions. .</ P> <P> impact process </ P> <P> for the upcoming case of "Deep Impact" process and associated data, the CAS Shanghai Astronomical Observatory of astrophysics Professor Zhao said that NASA, Eastern Time .This year at 13:47 on January 12 launched a called "Deep Impact" probe. .</ P> <P> 24 hours before the collision in the implementation, "Deep Impact" spacecraft will accurately measure the impact the specific location of the comet, the comet at a distance of 500 kilometers release an impactor, and guide it into the "Temple .1 "comet's orbit. .</ P> <P>, the impactor and the power plant through its own navigation through the "Tempel 1," the tail of a comet, coma, about 37,000 km per hour speed of about 6 km to the diameter of the comet rushed, .--- straight to the core of the comet nucleus. .</ P> <P> At this point, the detector will change the route, the flight arrives after 500 km away from the comet's closest point. .U.S. Eastern Daylight Saving Time at 1:52 on July 4, the impactor and Tempel 1 comet will be in place 132 million km from Earth collided and knocked at the comet surface to a depth equivalent to 14 stories tall, nearly 200 .meter-wide pit. .The moment of impact will spray a lot of dust, and within a few hours after impact, the comet will brighten 15 to 40 times. .</ P> <P> what it means </ P> <P> Zhaojun Liang believes that "Deep Impact" is much more than a luxury NASA director of "Independence Day fireworks show", it has a more profound scientific significance. .</ P> <P> one sense, human beings can comet Tempel 1 by the internal structure, access to the origin and early evolution of the solar system clues, and then explore the secrets of the solar system. .Meaning of the Second, by studying the internal structure of comets, especially the use of the impact of the collected material contains information about the depths of the nucleus, we can more fully identify and understand the two "origins of life" theory. .</ P> <P> where the origin of life, the origins and academia there are two completely different views. .A technology called "local said," that life on Earth originated in the Earth's local, that is, the birth of life on earth and continue to evolve. .Another called the "external source said," and advocate the origin of life on Earth than the Earth, the first material can form life does not exist in the local earth, but from the earth outside the "import" the. .Advocates of life on Earth, "germ" comes from outside the Earth view, the early life of Earth itself is not required for the formation of compounds. .However, the formation of life some of the complex organic molecules required already exist in interstellar space or interplanetary space; they attach to their small bodies in the solar system (including asteroids and comets), and these small bodies or their fragments and particles are often .into the earth, so as to bring about the formation of the Earth need the original germ of life --- organic compounds. .</ P> <P> If the detector to detect the substance from the nucleus of these organic molecules, the study results will likely be the origin of life "outside source said" a big support. .Of course, if in the future can do the comet material back to Earth, then the whole process of sample collected must be isolated from the implementation of sealing to ensure that their "extraterrestrial matter," the property. .</ P> </ p>.